This invention relates to the processing of substantially rigid elongate foam boards which are used as insulation panels at construction and roofing sites and need to be accordion folded so that they can be more readily transported to the site.
The present invention provides a method which is well suited to use in a plant utilizing a laminating machine to produce a board which is provided on its upper and lower surfaces with a cover film and then cut into elongate lengths which are fed to an elongate slitting machine upstream of an accordion folding station where folding may be accomplished manually or mechanically.
The board to be processed comprises a closed cell foam board bounded on each of its upper and lower surfaces by facer strips comprising a Kraft paper facer bonded to the core foam and having an outer plastic cover facer film bonded to it.
It is an important object of the present invention to provide an improved and economic method of treating the foam board, which may be in the nature of a half-inch in thickness, to provide alternating upper and lower slits, which do not extend all the way through the composite board, at preselected longitudinal intervals to provide folding sections in a precision manner.
A further object of the invention is to provide a highly reliable method and apparatus which rapidly and efficiently handles the foam board in a manner which does not result in undue down time in the production line.
The invention is concerned with a method of and apparatus for treating foam board to so slit it as to permit its ready accordion folding without the creation of undue quantities of scrap. The board is moved along a longitudinal pathway, at a temperature which is less than a temperature which would deform the substantially rigid foam board, into a slitting machine. After traveling into the machine, the board is stopped and clamped in stationary position and laterally moving longitudinally uniformally, spaced upper and lower slitting members which provide slits less than the thickness of the overall board, move laterally across the board to provide folding sections in the board. The board is then released to travel to a folding station where accordion folding takes place.